Mining machine feeding mechanism



y 1951 c. P. BALDWIN 2,552,705

MINING MACHINE FEEDING MECHANISM Filed March 26, 1945 2 Sheets- Shee t 1 May 15, 1951 Filed March 26, 1945 C. P. BALDWIN MINING MACHINE FEEDING MECHANISM 2 Sheets-Sheet2 different feeding speeds.

to provide an improved fluid operating driving Patented May 15, 1951 MINING MACHINE FEEDING MECHANISM Clyde P. Baldwin, Claremont, N. H., assignor to Joy Manufacturing Company, a corporation of Pennsylvania Application Mar-ch 26, 1945, Serial No. 584,967

3 Claims.

This invention relates to mining machines and more particularly to improvements in the flexible feeding mechanism of a coal mining machine of the floor type.

An object of the present invention is to provide an improved coal mining machine. Another object is to provide an improved flexible feed ing mechanism for a floor type coal cutting machine. A furl-her object is to provide an improved feeding mechanism embodying a feed operating member having a flexible feeding element cooperating therewith and improved means for driving the feed operating member at Yet another object is means for the feed operating member. A still further object is to provide an improved hydraulically operated driving means for the flexible feeding means of a coal cutting machine. Still another object is to provide an improved hy draulically operated driving mechanism embodying a pair of cooperating hydraulic motors for independently or concurrently driving the flexible feeding means. A further object is to provide an improved feed operating member-driving system including a pair of driving motors each having a driving gear meshing with and driving a common gear connected to the feed operating member, whereby, at times, the latter may be driven at one speed by but one motor, and, at other times, at a different speed by both motors. Still a further object is to provide an improved hydraulically operated feeding mechanism embodying a pair of hydraulic driving motors and pumping means capable of supplying to either or both of said driving motors at the will of the operator different quantities of operating fluid per unit of time. Still another object is to provide an improved hydraulically operated feeding mechanism embodying a pair of hydraulic driving motors and a dual capacity pump for supplying liquid unde pressure in different volumes to either or both of said motors thereby to vary the speed and Winding torque of the feed operating member. These and other objects and advantages of the invention will, however, hereinafter more fully appear.

From a broad aspect, my invention ma be embodied in an apparatus including an element to be rotated to efiect feeding, a plurality of motors each operatively connected with said element to effect rotation thereof and adapted either separately or concurrently to impart torque thereto, and a fluid pumping and delivering system for effecting the delivery to either or both of said motors of difierent desired quantities of operating fluid; and in a preferred embodiment a multiple-unit pump including pumping units of different capacities may be employed, together with means for delivering the fluid from either or both units to one or more feed effecting element-operating motors; and desirably, the output of each pumping unit, when a multiple unit pumping apparatus is employed, will be different from the fluid requirements at normal full load speed of each of the winding element operating motors.

In the accompanying drawings there is shown for purposes of illustration one form which the invention may assume in practice.

In these drawings:

Fig. 1 is a plan view, with parts in horizontal section, of a coal mining machine with which an illustrative form of the invention is associated.

Fig. 2 is an enlarged horizontal sectional View, illustrating the improved feeding mechanism.

Fig. 3 is a cross-sectional view taken on line 33 of Fig. 2.

Fig. 4 is an enlarged hrizontal sectional view taken through one of the control valve devices.

Fig. 5 is a diagrammatic view of the hydraulic system.

In this illustrative embodiment of the invention, the improved feeding mechanism is shown associated with a longwall coal cutting machine. Evidently the invention may be associated with coal cutting machines of other sorts.

The coal cutting machine comprises a machine frame I slidable on its bottom 2 over the door of a mine and having a horizontal cutter bar 3 projecting laterally from one side of the machine frame during the cutting operation. The machine frame includes a central motor section 4, a front feed frame section 5 and a rear cutter frame section 6, and the cutter bar is pivotally mounted on the frame section 6 to swing horizontall relative thereto from a position extending lengthwise of the machine frame, as indicated in dotted lines in Fig. 1, to the right angle position as shown in full lines in that figure. Arranged within the feed frame section 5 is a rotatable feed operating member 1 herein preferably a horizontal feed drum on which a feed cable 8 is wound. The feed cable may be attached to the cutter bar to swing the latter about its pivot, and a conventional lock 9 is provided to lock the cutter bar in its adjusted positions with respect to the machine frame. The feed cable, when detached from the cutter bar, may be extended forwardly along the coal face with its remote end connected to an anchor jack in advance of the machine, and, when the feed cable 8 is wound in by the feed drum l, the machine is fed bodily along the coal face to out a horizontal kerf beneath the coal. Since the general structure and mode of operation of a 'longwall coal cutter is well known to those skilled in the art, further description thereof is herein unnecessary.

In the drawings, it will be observed that I have illustrated a pumping mechanism of the plural unit type, and it will be seen that driven from the power shaft it of the motor is a liquid pump I I of multipleherein triple-capacity, arranged Within the feed frame section and including a low capacity unit 52 and a large capacity unit E3. The pump intakes are connected to a liquid tank I4 arranged within the feed frame section,. and the pump discharges are connected through control valve devices and it to a pair of hydraulic motors I"! and !8 respectively, likewise arranged within the feed frame section. These motors are of'a conventional design and their power shafts are coupled at 9 and 253 to longitudinally extending horizontal shafts 2i and 22 preferably coaxial with the motors and herein arranged in parallelism on. axes spaced equidistantly from the longitudinal center of the machine frame at the opposite sides of the .latter, as clearly shown in Fig. 2. Secured to these parallel shafts and driven thereby are worms 23 and 24 respectively meshing with worm wheels 25 and 26 herein arranged on parallel vertical axes at the outer sides of the shafts 2i and 22 respectively. These Worm wheels are connectible by shiftable jaw clutches 2'! and 28 respectively to vertical shafts 29 and 3B. These vertical shafts carry at their lower ends gears 32 and 33 meshing with a large internal gear a l secured to the feed drum "1. The gears 32 and 33 preferably mesh with the drum gear 3! at diametrically opposite points as shown clearly in Fig. l.

The hydraulic system, as shown diagrammatically in Fig. 5, shows the pump'intakes connected by branch conduits 35 and 36 to a conduit 3'5 leading from the liquid tank [4. The discharges of the pump units l2 and i3 are connected by conduits 38 and 39 to the control valve devices it and 26 respectively. The pressure conduits 38 and 38 are connectible through relief valves 4t and M to branch conduits t2 and in turn connected to a return conduit 44 leading to the tank Hi so that, when the pressure in the system becomes excessive, the relief valves will open to discharge the liquid in the pressure lines back to the tank. The control devices [5 and !6 respectively, as shown in Fig. 4, include valve blocks 35, 6 and 4?, 38 each containing a conventional manually operable control valve V. Extending between the valve devices it and i6 is a conduit 49 for connecting the discharge side of one to the discharge side of the other, and a discharge conduit 59 connects the conduit 49 to the tank i l. The valve block is connected by conduits 5i and 52 to the opposite sides of the motor 51, and the valve block 68 is connected by conduits 53 and 54 to the opposite sides of the motor I 8. Conduits 55 and 56 lead from. the valve block 46 to the opposite sides of the motor I8, and the valve block ll is connected through conduits 5i and 58 to the opposite sides of the motor ll. Each pair of valve blocks 15 and It includes an inlet passage 59 connected through a supply conduit with the discharge of a pump unit l2, it.

The inlet passage 559 communicates with parallel passages 60 and 6| and with central bypass passage 62 leading to a longitudinal discharge passage 63 connected to the discharge conduit 49. The blocks have end passages 64, 64 communicating with the discharge passage 53. Each slide valve has spaced spools separated by circumferentially extending grooves 65, 66 and 61. Formed in the walls of the bores receiving the slide valves are annular end grooves 58, 68, to which the conduits leading to the motors I1 and I8 are connected. When the slide valves are in neutral position, as shown in Fig. 4, fluid under pressure in the inlet passage 59 is bypassed through the central passage 62 to the discharge passage 63. When the slide valves are slid in one direction or the other, the central bypass 62 is closed by one of the intermediate spools of each valve,v and end grooves or 61 in the valves connect one of the supply passages 80 with the grooves 68 at one end of the valve-receiving-bores. For example, when both slide valves of the valve devices 15 are moved to the extreme left in Fig. 4, fluid under pressure is supplied from the low capacity pump unit I2 through conduits 5| or 55 to both motors I7 and I8, and when the valves are both slid to the extreme right in Fig. 4, fluid under pressure is supplied through conduits 52 or 56 to the opposite sides of the motors to effect running thereof in the reverse direction. By independently operating the valves, the motors I1 and 18 may be separately operated in either of opposite directions. Also, the valves of the valve device it may be operated in a similar manner to supply fluid under pressure from the large capacity pump unit It either separately or simultaneously through conduits 53 or 5'! to run the motors in one direction or either separately or simultaneously through conduits 54 or 58 to run the motors in the reverse direction. The slide valves of both valve devices i5 and I6 may be positioned to supply fluid under pressure from both pump units 52 and i3 to either motor or to both motors, and likewise by oppositely positioning the valves, both valve units may supply fluid under pressure to both motors to run the latter either separately or simultaneously in the reverse direction. Of course, when but one motor is driv' in the drum 1, the other motor is disconnected from the drum by releasing the proper clutch 21, 28, and when both motors are driving the drum,

' they run in the same direction, thereby cooperating to turn the drum in one direction. Accordingly the discharge from either or both pump units I2, I3 may be connected under the control of the valve devices I5 and i6 to either or both of the motors H and it. And either motor may obviously be driven separately in either direction or both may be driven together in either direction, and the several valve devices are'so constructed that when fluid is being supplied to either side of either motor the other side of such motor is connected back to the tank M.

It will be evident that by using the fluid from the low capacity pump IE only, and dividing its discharge between both motors I! and it, a high torque with a very slow speed may be secured. If all of the fluid from the low capacity pump is delivered to either motor separately, twice as great a winding speed may be secured. If the fluid from the large capacity pump be delivered simultaneously to both motors, a higher Winding rate with high torque will be secured; and if the fluid from the large capacity pump be delivered to but one motor at a time, the winding rate last mentioned will be doubled and the torque reduced correspondingly. It will also be noted that the discharge from both pumps can be delivered to the two motors or to one of the same, with resultant additional speeds. If the discharge of the pump 13 is not equal to just twice that of the pump I2, at least six speeds can be secured, with the various uses of pumps with one or both, motors, and so a wide range of conditions can readily be m t. By the provision of pumping apparatus adapted under operator control to supply fluid in different quantities per unit of time to either or both of the drum operating motors, there can obviously be secured a wide range of Winding speeds and thus an improved adaptability of the coal cutting machine to variable conditions.

As a result of this invention, an improved mining machine feeding mechanism is provided wherein the feed operating member may be driven at relative different speeds in an improved manner. It will further be evident that by the provision of a pair of driving motors which may be separately or simultaneously connected in drivin relation with the feed operating member, the latter may be driven relatively more slowly and powerfully or may be driven relatively more rapidly but with less power at a relatively higher speed, and, depending on what pump outputs are used, securing various speed ranges. Further, by the provision of the triple capacity pump, the pair of hydraulic motors, and the improved control valve means, driving of the feed operating member is substantially improved. Moreover, the speeds of drum rotation and the winding torque may be varied as desired. Other uses and advantages of the invention will be clearly apparent to those skilled in the art.

While there is in this application specifically described one form which the invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration, and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a mining machine feeding mechanism, the combination comprising a feed operating member adapted to cooperate with a flexible feeding element, and motor operated driving means for said feed operating member including -a pump, a pair of fluid motors deriving their fluid supply from said pump, a gear rotatable with said feed operating member, separate gear trains driven by said motors respectively and each having a terminal gear meshing with and driving said feed operating member gear, and control valve means including separate control valves for individually controlling said motors whereby one or both of said motors may drive said feed operating member.

2. In a mining machine feeding mechanism, the combination comprising a feed operating member adapted to cooperate with a flexible feeding element, and motor operated driving means for said feed operating member driving the latter at either a high or a low speed including pumping means of dual capacity providing a small capacity discharge and a large capacity discharge, a pair of fluid motors, a gear rotatable with said feed operating member, separate gear trains driven by said motors respectively and each having a terminal gear meshing with said feed operating member gear, and control valve means for connecting either discharge or the combined discharges of said pumping means to either fluid motor, said control valve means including means for individually controlling said motors whereby one or both of said motors may drive said feed operating member.

3. In a mining machine feeding mechanism, the combination comprising a feed operating member adapted to cooperate with a flexible feeding element, and motor operated driving means for said feed operating member driving the latter at either a high or a low speed including pumping means of dual capacity providing a small capacity discharge and a large capacity discharge, a pair of fluid motors, a gear rotatable with said feed operating member, separate gear trains driven by said motors respectively and each having a terminal gear meshing with said feed. operating member gear, and control valve means for connecting the small capacity discharge to either motor or for connecting the large capacity discharge to either motor, said control valve means including means for said motors for individually controlling the latter whereby one or both of said motors may drive said feed operating member.

CLYDE P. BALDWIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,639,255 Brackett Aug. 16, 1927 1,682,358 Sperry Aug. 28, 1928 1,905,145 Carter Apr. 25, 1933 1,922,293 Holmes Aug. 15, 1933 1,932,760 West Oct. 31, 1933 2,103,530 Henry Dec. 28, 1937 2,229,086 Joy Jan. 21, 1941 2,257,108 C'ornwell Sept. 30, 1941 2,308,451 Lindgren Jan. 12, 1943 2,323,493 Sloane July 6, 1943 2,345,662 Fox et a1 Apr. 4, 1944 FOREIGN PATENTS Number Country Date 26,279 Great Britain Nov. 15, 1912 421,296 Germany Nov. 9. 1925 

